When the setting calls for a classy yet killer getup, try pairing a navy pea coat with chinos. Dark brown brogues will infuse a touch of polish into an otherwise utilitarian outfit. Outfits like this have a refined air that befit gentlemen in their forties very well.
For an ensemble that's city-style-worthy and casually classy, pair a tobacco overcoat with chinos. And if you need to immediately bump up this look with a pair of shoes, why not complete your look with dark brown brogues? All in all, a great demonstration of smart casual style for guys in their 40s.